(a) It shall be the duty of the committee to investigate supply and demand conditions for grades, sizes, and qualities of all potatoes. Whenever the committee finds that such conditions make it advisable to regulate the shipment of particular grades, sizes, or qualities of potatoes during any period in any or all portions of the production area, it shall recommend to the Secretary the particular grades, sizes, and qualities, or any combination thereof, of such potatoes deemed advisable to be shipped during such period: Provided, That the committee shall not recommend to the Secretary any regulation limiting the shipment of U.S. No. 1 grade or better, as such grades are defined in United States Standards for Potatoes in effect at the time of recommendation.
(b) In determining the grades, sizes, and qualities of potatoes or any and all combinations thereof deemed advisable to be regulated in view of the prospective demand thereof, the committee shall give due consideration to the following factors:
(1) Market prices, including prices by grades and sizes, of potatoes for which regulation is recommended;
(2) Potatoes on hand in the market areas as manifested by supplies en route and on track at the principal markets;
(3) Available supply, quality, and condition of potatoes in the production area and other production areas;
(4) Supplies from competing areas and regions producing potatoes;
(5) The trend and level of consumer income; and
(6) Other relevant factors.